My barometric pressure readings go through a cycle every day that I am pretty sure is not really happening. Every day just before 0600 the barometric pressure reading starts rising sharply and goes up 12-15 mb in an hour. Then it spends the next 23 hours gradually going down until it shoots up again the next day.

The pressure readings at nearby NWS stations and personal weather stations do have a diurnal cycle, but it's not the same. They have more of a sine wave looking pattern with a gradual high around late morning and a gradual low in late afternoon.

Has anybody else seen this or have a theory why it would be happening? I'm not sure if it's happening in the software or in my weather station.

Just for grins I moved the base unit a little farther away from the window and put a shoebox over it to try to shield it from any environmental factors. We'll see tomorrow morning if it makes any difference.

During a period of little actual change in pressure, I've caught my WH3081 (rebadged as "PanTech") showing the temperature dependence of its pressure sensor with inside temperature. It goes through this cycle every day as the reverse cycle air conditioner kicks in and stops for a short time as its outside unit temporarily freezes up.

press-temp.png

It looks like there's a close to +0.36 hPa/°C pressure reading variation. I expect that Steve has very little available time, but it would be great if he could add the option of a -0.36 hPa/°C compensation option for FO weather stations to the calibration page which would mostly null out this annoying error.

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